Nato says its overnight air strikes have inflicted further "serious damage" on the Yugoslav war machine.

More than 60 Nato warplanes took part in a second night of air strikes on Yugoslavia over the Kosovo crisis.

The UK Defence Secretary, George Robertson, told a news conference that the raids had been successful.

He said the attacks would not cease until the Yugoslav leader, President Slobodan Milosevic, ended the violence in Kosovo.

American B-52 bombers have taken off from their base at Fairford in the UK. It is not clear whether they are mounting more air strikes, but air-raid sirens have been sounding in the Kosovan capital, Pristina, and the northern city of Novi Sad.

Military chiefs described Thursday night's attacks on Yugoslavia as significantly heavier than on the first night.

Numbers of casualties are difficult to verify, but Russia's RIA news agency quoted Yugoslav figures as showing on Friday that Nato bombing had killed more than 100 civilians and 30 soldiers.

RIA also said that more than 350 people in Yugoslavia, most of them civilians, had been wounded after the second night of bombing.

Nato rifts

With Nato action appearing to enter a third day, there were signs of a possible split in the alliance itself.

Greece has called for an end to the bombing. Government spokesman Yannis Niolaou is reported as saying: "It is time to go back to political dialogue to seek a political solution to the problem and to stop the bombing."

Serb TV reports on the strikes

Italy has called for the attacks to be short-lived. Prime Minister Massimo D'Alema said he wanted Nato's actions to be brief and focused on objectives.

He expressed firm support for the alliance and said the action was inevitable, but called on Russia to help bring a "faster
reopening of negotiations".

Russia has ordered the alliance's two top representatives in Moscow to leave the country as part of a freeze on all contacts with Nato because of its raids on Yugoslavia.

Nato's top diplomatic official in Moscow, Alexis Chahtahtinsky,
and its senior military representative, Manfred Diehl, were
told to leave Russia on Friday, according to Russian Foreign Minister Igor Ivanov.

Russia has forced the Security Council to vote on Friday afternoon on whether the strikes are legal.

Serb offensive

Despite Nato's attacks, Serbian forces are reported to have continued their offensive against Albanian targets in Kosovo and in Albania.

Mr Robertson said Serbian forces had shelled two villages
in Albania on Thursday, and a third village in Kosovo was surrounded by Serb forces and shelled with the population unable to leave.

The Kosovo Albanians said there was heavy fighting on Thursday west of Pristina and to the north, and that 20,000 civilians were surrounded by tanks in the northern village of Qirez.

Serbian reports say the separatist Kosovo Liberation Army (KLA) has been using the cover of Nato strikes to launch attacks on Serbian positions.

Violence has spilled beyond Yugoslavia in protest against the Nato action, in the form of attacks on Western embassies and representative offices in neighbouring Macedonia and Bosnia, and in Moscow and Canada.

The BBC's World Affairs Editor, John Simpson, one of the few remaining journalists in Yugoslavia after the expulsion of reporters from Nato member countries, says the Serbs feel victimised by the West.

"They feel absolutely bitterly betrayed by the bombings. It's an attitude that goes right across the whole of society."

US President Bill Clinton made a direct address to the Yugoslav people to explain Nato's actions against their country.

He told them that the alliance had no quarrel with them and that they should blame their leader, President Milosevic, for what was happening.

Yugoslavia has broken off diplomatic relations with the US, Britain, France and Germany.

Yugoslav Deputy Prime Minister Vuk Draskovic said they would cease all operations against the Kosovo Albanians if Nato stopped its bombing.

Cruise missiles

More than 60 Nato planes, including US stealth bombers, F-15 and F-16 fighter jets and RAF GR7 Harriers, took part in Thursday night's raids.